The checking of geometrical constraints on integrated-circuit layouts is notoriously slow and costly when carried out purely by software. This paper introduces a new approach, in which layers are converted into digitised pictorial form and processed by simple hardware operating like a computer peripheral. This hardware reports to the computer all cases where constraints may be violated, and these ...
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The fast Fourier transform (f.f.t.) has found wide applications in areas requiring the processing of uniformly sampled signals. This paper investigates the characteristics of using a standard, inexpensive micro-computer system to implement an f.f.t. processor operating in either real-time or online mode. Various aspects on the maximum sampling rate in either mode of operation, such as the limitati...
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A procedure is described which can be used to design digital differentiators satisfying prescribed specifications. The procedure is based on the Fourier-series method for the design of nonrecursive digital filters, and uses the Kaiser window function for the minimisation of the amplitude of Gibbs oscillations. The approach is used to design a number of differentiators assuming various prescribed b...
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A technique is described for the optimal synthesis of n-variable combinational logic circuits with Multiplexer universal logic modules, which may readily be implemented without excessive computer storage requirements. The method requires knowledge of the Rademacher-Walsh spectrum, which is an alternative representation of the truthtable vector of the function being considered. It makes use of a pr...
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